Vesicular transport: how many Ypt/Rab-GTPases make a eukaryotic cell?

Trends Biochem Sci. 1997 Dec;22(12):468-72. doi: 10.1016/s0968-0004(97)01150-x.


In eukaryotic cells, protein transport through the secretory and endocytic pathways is mediated by vesicular intermediates. Individual transport steps are regulated by Ras-like guanine nucleotide-binding proteins, termed Ypt in yeast or Rab in mammals. The complete sequencing of the Saccharomyces cerevisiae genome has revealed the total number of Ypt GTPases in this organism. There is some redundancy among the 11 Ypt proteins, and only those involved in the biosynthetic pathway are essential for cell viability.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Biological Transport
  • Conserved Sequence
  • Endoplasmic Reticulum / metabolism
  • Eukaryotic Cells / metabolism*
  • GTP Phosphohydrolases / metabolism*
  • GTP-Binding Proteins / metabolism*
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins*
  • rab GTP-Binding Proteins*


  • Saccharomyces cerevisiae Proteins
  • GTP Phosphohydrolases
  • GTP-Binding Proteins
  • YPT1 protein, S cerevisiae
  • YPT7 protein, S cerevisiae
  • SEC4 protein, S cerevisiae
  • rab GTP-Binding Proteins